Plant for the manufacture of cement



March 26, 1929. T. RIGBY PLANT FOR THE MANUFACTURE OF CEMENT Original Filed July 20, 1925 2 sheets-Sheet mmmwm 5 jlllllllll/fllll/IYI V llllllll/l/l /[4/// vii/I111 Inuenhr- 949 March 26, 1929. BY 1,706,750

PLANT FOR THE MANUFACTURE OF CEMENT Original Filed Ju}y 20, 1925 2 sheet -sheet 2 Patented Mar. 26, 1929.

UNITED s A TES THOMAS RIGBY, OF LONDON, ENGLAND.

PLANT FOR THE MANUFACTURE OF CEMENT.

Original application filed July 20, 1925, Seria1 No. 44,865, and in Great Britain July 28, 1924. Divided and this application filed March 9, 1927. Serial No. 174,071.

This invention relates to plant for making cement by the wet method and consists 111 improvements in such plant the nature of which will become evident to those skilled in the art from the following description of an illustrative example of plant accordingto the invention, the features of which are explicity pointed out inthe appended claims.

In the accompanying drawings Figure 1 shows in sectional side elevation the general arrangement of one former installation according to the invention;

Figure 2 is a sectional plan of part of the installation shown in Figure 1 Figure 3 shows in sectional side clevation. but to an enlarged scale, part of the installation shown in Figure 1;

Figure 4 illustrates how in a case such as that shown in Figure l, the kiln head may if desired be utilized as a kiln gas cooler and washer; and i Figure 5 is an end view of the upper hoodholding ring of Figure 3 as seenwhen' looking from the right in that figure.

In Figures 1 and 2 the upper end of the kiln is shown at 3 opening into the kiln head through the rear wall 5 of which (see also Figure 3) three slurry spraying nozzles 6, 7 and 8 are shown as operating. the spray into the kiln (through the gas space of the kiln head) to different distances, the spray from the nozzle 6 being shown diagrammatically as opening out to the internal kiln diameter at about a, a, at about 6, b, and that from the nozzle 8 at about 0, 0. Thenozzles are set at a slight angle to one another so as to converge and to compensate for the fact that none of them is axial with the kiln and the spraysfrom them intei'penetrate to a certain extent, that which reaches to 0, 0 passing for instance through the two others. The sprays enter the gas space 9 through circular openings (see 11 Figure 3) in the end wall of a chamber 13 adjustable axially of the kiln in an opening 15 (Figure 2) in thewall. 5. Each nozzle is secured upon a carriage .17 by adjustment of which (by rotation of a screw 19) the nozzle may be adjusted axially relatively to'a tubular hood 21 (in which the screw is held against axial movement) and through an opening23 in the end wall of which the spray from the nozzle passes tothe'opening. 11 in the end wall ofthe chamber 13. Openings (not shown) are provided in the lowest por- These proj ectr that from the nozzle 7 of the spraying tion of thehood through which slurry collect:- ing in the hood may drain out into a discharge trough 25. The hood is held adjustably in position in the chamber 13 by three or more clamping screws 127 extending against it radially from a ring 27 secured to the chamber and this arrangement enables the hood and jet to be adjusted readily to any desired angle with the axis of the kiln for the correct projection of the spray to its zone in the kiln. A stud 29 may project from the end wall of the hood to assist, by contact with the end wall of the chamber 13, in locating the hood axially. The tubular hood 21 with its opening 23 relatively to which thenozzle is adj ustable is an example of means which may be conveniently used to control the amount of atomized material entering the kiln by using an apertured plate or battle in the path of the spray to control the proportion of the spray issuing from the nozzle which it is desired shall be admitted to the kiln. Any portion of the spray which strikes the baffle will not pass into the kiln but will coalesce and become slurry again which flows away from the kiln by the troughs 25. i v c I With the arrangement shown in which the screws 127 lock the hood 21 in position with the stud 29 contacting with the end wall of the chamber 13, it is possible to withdraw any of: the spraying devices from the chamber 13 for inspection or cleaning without'loss of the relative setting of the said devices. slacking off one of the, screws 127 will free the hood 21 which can be then removed bringing away with it the spraying device the end piece of which can then be removed, if necessary, through the opening 23. Any desired inspection or cleaning having been effected the hood is put back with its stud 29 once more in contact with the end wall. of the chamber 13 so that the hood rests on the two screws 127 that have not been disturbed, and the unit comprising the hood and spraying device having been thus restored to its former location axially of the chamber 13 and with the axis device having its former relation to the axes of the other spraying devices, the hood is then locked in place once more by tightening again that screw 127 which had been slacked oii.

The provision of a chamber such as 13 with an opening such as 11 through whlch the spray of slurry passes into the kiln head and tl'nrough the gas space thereof to enter vice from exposure to the gases and the heat thereof and making it readily accessible for attention so that the device remains free from *aked slurry or deposits on 1t 0t material from the gasesand is at all times cool and I easily handled at a moments notlce. Such an arrangement is to be regarded,- however, mercly as illustrative of one of many ways in which a sin'iilar result may be secured since, for example, to secure a device that projects slurry in an atomized or similarly dispersed condition into a rotary kiln shall be guarded from the gases and the heat thereof and be at all times convenient for attention to, it no more need be necessary than to provide an opening in the rear wall of the kiln head more or less in line with the kiln mouth and outside which the device operates to project the slurry through that opening and so into the kiln.

The slurry is preferably fed to the nozzles by an arrangement that ensures the requisite differences of pressure or head at the nozzles being as far as possible maintained at all times during the working. This is best achieved in a simple way if a single slurry pressure feed system be used for all the nozzles and the various nozzles fed by tapping for each one that system at a point in it where the proper head prevails. Thus-for example a slurry force pump may feed the slurry along a conduit to an exit and the conduit be divided between the pump and eXit by suitable conlbs. per square inch so that for example one nozzle may be connected to a section at a pressure of some lbs. another nozzle to one at a pressure of some 50 lbs. and so on. Alternatively a slurry pump may raise the slurry to an open tank at a given height abovethe kiln and from which slurry may flow both to one of the nozzles and to another open tank at a lesser height above the kiln from which latter tank slurry may flow both to the second nozzle and to yet another tank still above the kiln level and so on.

In Figure 4 the kiln head shown as converted into a reservoir for slurry over which the gases from the kiln are caused to pass in flowing down between the rear wall 5 of the head and the front wall 35 of the latter and up behind the wall 5 and over the wall 87 away to the chimney, this slury (Which is fed in through an inlet 33) being kept stirred by compressed air from pipes indicated at 39 and withdrawn from a well 41 outside the kiln head and into which well the slurry passes through an opening 43 below the levels of the liquid in the reservoir and well.

Where the slurry from the well 41 is used to feed the spraying nozzles of the kiln this slurry obviously becomes advantageously concentrated (by actual evaporation of water from it and also by cement material carried out of the kiln by the gases) before being passed to the kiln. If weak slurry is used and it does not by the admixture with it of deposited matter and evaporation of its water reach a condition which its it for supply, if desired, to the kiln it may be used in the slurry making installation of the plant so that its contents of cement materials shall not be wasted. Such an exposure of the gases to slurry in passing from the kiln to the chimney will in most cases cleanse these gases from cement dust better than the means ordinarily in use in cement plants. The exposure of the gases leaving the kiln to the cleansing and cooling action of slurry may be effected by exposing the gases outside the kiln to slurry in an atomized or similarly dispersed condition. While this may be done in a specially provided gas cooling tower or the like to which the gases pass from the kiln head the smoke chamber in the kiln head itself may be made use of by providing instead of or in addition to acontainer for liquid as has been above mentioned, suitable slurry atomizing or like dispersing means such for example as one or more slurry spraying nozzles directing a spray or sprays down the kiln head from, and it may be through, one or more openings in the kiln head at or near its top.

The slurry may either be passed through the gas contact space outside the kiln and forthwith utilized as desired or it maybe continuously withdrawn from the said space and returned to it anew only a portionof'the circulating slurry being continuously or from time to time withdrawn for use as desired and this loss made good by the addition of fresh slurry to the circulating bulk; Any slurry enriched from the gases by material carried out of the kiln thereby should be very thoroughly mixed before being passed to the kiln and accordingly it may be desirable after any such slurry is withdrawn from the device in which it is exposed to the gases from the kiln and preferably before such withdrawn slurry passes to a slurry pump or the like supplying the spray nozzles or like device, to sub ect 1t to mixing or grinding and m1X1ng treatment.

A pipe 45 is shown in Figure 4 dipping into the liquid in the well 41 and this pipe leads to a pump 47 discharging through a pipe 49 into a slurry supply tank 51 into which the main supply of slurry is fed through a pipe 53 and from which tank the slurry received from the pipes 49 and 53 passes by a pipe 55 to a pump 57 and thence by a pipe 58 and branch pipes 59 to the spray nozzles.

Instead of compressed air being usedfor agitating the slurry, paddles or their equivalent may be used in any desired combination and it may in some cases be advantageous to arrange that the container for slurry which collects the material carried out of the kiln by the gases is partly in the kiln head and partly outside the head to facilitate provision of stirring and mixing devices.

I claim:

1. A cement making plant comprising a kiln in the form of a hollow cylinder with open ends having its axis inclined slightly to the horizontal and rotatable about that axis, and a stationary chamber having side walls provided with openings into the open ing in one of which the open upper end ofthe. kiln projects, said chamber also having agas outlet, together with a plurality of independently adjustable spraying nozzles located in the opening in the side wall of said chamber opposite the first mentioned side wall, said nozzles being in line with the open end of the kiln and arranged to project sprays across the said chamber and into the open upper end of the kiln along convergent axes.

2. A cement making plant comprising a kiln in the form of a hollow cylinder with open ends having its axis inclined slightly to the horizontal and rotatable about that axis, and a stationary chamber having side walls provided with alined openings into one of which the open upper end of the kiln projects, said chamber also having a gas outlet, a spraying nozzle located in the opening in the side wall of said chamber opposite the first mentioned side wall, said nozzle being in line with the open end of the kiln and the opening in said opposite side wall extending about the nozzle and spaced therefrom to admit air into the chamber about the nozzle and the nozzle being disposed out of the path of gases passing through the chamber. said nozzle being arranged to project a spray across the said chamber and into the open upper end of the kiln.

3. A cement making plant comprising a kiln in the form of a hollow cylinder with open end having its axis inclined slightly to the horizontal and rotatable about that axis, and a stationary chamber having side walls provided with openings therein into .one of which the open upper end of the kiln projects, a hood mounted in another opening in the side wall of said chamber opposite the first mentioned side wall, said hood having an opening through its inner end facing the upper open end of the kiln, and a nozzle adj ustably mounted in the hood for adjustment which the open upper end of the kiln projects, a spraying nozzle located in the opposite opening in the side wall of said chamber opposite the first mentioned side wall, removable adjusting means for the nozzle mounted in said opposite side wall and adapted to adjust said nozzle in line with the open end of the kiln to project a spray across said chamber and into the open upper end of the kiln, said removable adjusting means for the nozzle adapted to be removed with the nozzle from said opposite side wall of the chamber without disturbing the adjustment of the nozzle with respect to said means.

5. A cement making plant comprising a kiln in the form of a hollow cylinder with open ends having its axis inclined slightly to the horizontal and rotatable about that axis, and a stationary chamber having side Walls having openings therein into one of the openings the open upper end of the kiln projects, together with a casing fittingin the opening in the side wall opposite to the first mentioned side wall and having apertures therein facing the upper open end of said kiln, a plurality of hoods removably and adjustably mounted in said casing in line with said openings, a spraying nozzle mounted in each hood, means for axially adjusting and holding each spray nozzle in its respective hood, said adjusting means being independm ent of the casing and adapted for removal therefrom with the hood without disturbing the adjustment of the nozzle, said hoods and nozzles adapted for adjustment in line with the openings through the casing and in line with the upper open end of the kiln to project sprays across said chamber and into the open upper end of the kiln along convergent axis. 7

In testimony whereof I aflix my signature.

THOMAS RIGBY. 

